The 'DNA' singer let us in on her must-have foundation, her top shimmery blusher and her fave lipgloss for a plump pout.
She's also revealed the skincare brand she swears by to help combat spots, along with her biggest beauty regret and the products she can't live without.
Little Mix have a make-up range for Collection - do you have a favourite product?
"I am obsessed with the clear mascara. My lashes are so curly and thick, they're so annoying, so I use that and it really gets them in place. In the daytime I like to be as natural as possible. So during the day I will only wear clear mascara, I've got it on right now. It's perfect if you don't want to wear too much and just play it down. I just like being really natural, as natural as I can."
What's in your make-up bag?
L'Oréal Voluminous Mascara, £8.49
NARS Sheer Glow Foundation, £31
Little Mix by Collection Leigh-Anne's Bronze It!, £2.99
Bobbi Brown Long-wear Cream Shadow in Copper, £18.50
MAC Select Cover-up Concealer, £15
Bobbi Brown Shimmer Brick in Apricot, £32
Little Mix by Collection Leigh-Anne's Rock It Liner, £2.99
Yves Saint Laurent Golden Gloss, £22
Little Mix by Collection Leigh-Anne's Crystal Clear Full On Mascara, £2.99
MAC Lip Pencil in Stripdown, £12
Which products could you not live without?
"I cannot live without a bit of contour on my cheeks. I can't live without my lip balm. If I just want to chill but still want to look a little bit 'done up', I'll put lots and lots of lip balm on. It just looks more glossy."
Talk us through your beauty routine...
"My skincare is really important. I used to have really bad skin when I was younger. I'm a bit spotty now because I am tired. I've basically just got Aesop products. I am obsessed with them. I have the cleanser, the toner and the moisturiser. They have fixed my skin. It's important for me to feel comfortable with my skin. When I get spotty it just makes me not want to talk to anyone, so it's really important I look after my skin."
"My favourite is Lancôme La Vie Est Belle, £44 for 30ml, and I love Chanel Chance, £47.50 for 35ml, and Viktor & Rolf Flowerbomb, £49.50 for 30ml."
Have you picked up any make-up tips from the pros?
"Lots, I didn't have a clue how to put my make-up on before, I had no idea. My make-up artist taught me everything - how to use under-eye concealer and how to put gel liner on properly. Absolutely everything."
What's your biggest beauty regret?
"I used to wear really big lashes, I'd wear them on the [X Factor] shows and I look back and think, 'Why did I do that?' I looked horrible. My eyes are really small so I need lashes to fit them."
Do you have a fail-safe beauty look?
"On a normal day, I will put some mascara on and then just a nude lip, just keep it very natural really. I use my clear mascara to tame my brows, separate my lashes and keep my look really natural."
What do you like to do on a girls' night in?
"I love girls' nights in, me and my friends always do them. Nachos, we love our nachos. A good film. We talk about boys. My friend used to bring round her tarot cards and do readings. We do a lot of pranks as well."
How does it feel spending so much time in front of the cameras?
"We are used to it now. It's a part of the job. It is sometimes hard when you want to wear nothing on your face and slobber around, then out of nowhere there's a pap hiding behind the corner. You begin to embrace it though."
Want to know the other Little Mix girls' beauty secrets? Read about Perrie Edwards' tips here, Jade Thirlwall's fave make-up here, and Jesy Nelson's beauty regrets here!
Check out the full Little Mix by COLLECTION range at collectioncosmetics.co.uk and in store at Boots and Superdrug.
What do you think of Leigh-Anne's beauty routine? Let us know by commenting below as the best comment across the site each week wins £50!
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